Hello,
I am 17 years old and I was wondering if you guys could help me out. I just removed my old smog heads and I was looking to put on some better ones. One of the guys at school will sell me some heads for 40 bucks. They already have had work done to them and everything. My motor is a 350 bored .030 over and has flat top pistons. The valve sizes in the heads that I am looking at are 1.84 and 1.5. They are 58cc heads. The questions that I have are is that are the valves too small to run my motor at 5500-6000rpm. If so what is the highest rpm they can go. Also I was wondering if I will have any problem with detonation with these heads. If so I can run alittle race fuel too.

Sounds like 305 heads to me and they would bump your compression up on the 350 but they will never let the engine breathe. You would be sacrificing alot of power using them heads IMO 40 bux for a set of boat anchors is crazy.

unless of course they had a considerable amount of work i'd imagine. but for the rpm's your looking for i think elcamino350 is right, they wouldnt breathe good enough for you. what year engine do you have now? what car is this engine in?

The engine Block is from around 1977. It has been rebuilt before and has flat top pistons. It is in a 1972 El Camino with a th350 transmission, 2600 stall, and 4.10 gears with positraction. I also have a set of 993 heads, but they need alot of work, should I sink my money into those?

No. I have seen some good deals on Dart heads on Ebay. There are other places with good deals also but check Ebay first. Don't waste your money on the stock heads. Some of todays aftermarket heads are cheap enough that it isn't worth the work on the stock heads anymore.

if you have true flat tops with 4-valve reliefs with a quench of .040 with 58cc heads you would have 11.05:1 compression. You will likely have detonation issues. How bad depends on cam size, fuel, etc. I'd be looking for different heads.

I don't know what your original heads are or what the new heads have had done to them. If that guy at school had done anything to those heads that would make them worth using he wouldn't be selling them for $40. Don't let him talk you into them. If you want more power you will have better results with aftermarket heads. Save your money and buy some Darts or World products heads.

your 882's would give you 9.05:1 compression. It would definetly be more pump gas friendly. Weather or not they'll support your power goals depends on what you want. Also how much would you have to put in them to run them? I wouldn't put very much into them. Also many 882's are cracked due to them being thin.

I would save and do it right, if you go cheap you will not be happy with and do it over and it will cost 3 times the amount to to it right the first time.
It depends on how good the camel backs are, you will have to look closely for crack's. Are they 1.90 or 2.02 valves?
With that cam the RPMs will be OK but low in breathing for power.

Son, lesson to use old timers who have been doind this for 25 ,30 years . the new heads are ten times better that the old heads . If you get a set of old camle hump heads from some one. see if they will let you take them to shop. to see if they are good if they have the reworked it might cost you 200to400$. but you will have a good set of heads . I have a boat load of old camle hump's . Good luck. Keep with .70custon/10

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